This invention relates to a filament fabricated from a blend of ionomer resin and nonionic thermoplastic resin and to a melt extrusion (spinning) process for fabricating the filament. Among other applications, the filament is useful as a suture and as a surgical mesh.
Nonabsorbable sutures manufactured from various nonionic thermoplastic resins such as polyolefins, polyesters, polyamides, poly(esteramides), copolyether amides, polyether-polyester block copolymers, polyurethane block copolymers, and the like, are known. For further details regarding such sutures, reference may be made to U.S. Pat. Nos. 3,630,205 and 4,911,165 (sutures obtained by the melt extrusion of isotactic polypropylene), U.S. Pat. Nos. 4,520,822 and 4,620,542 (sutures made from ethylene-propylene copolymers), U.S. Pat. No. 4,557,264 (sutures made from blends of polypropylene and linear low density polyethylene), U.S. Pat. No. 4,621,638 (sutures made from polymers capable of forming hard elastic filaments under high stress spinning conditions, e.g., from polyolefins such as isotactic polybutylene, isotactic polypropylene, polyethylene and mixtures of isotactic and non-isotactic polyolefins), U.S. Pat. Nos. 3,297,033, 3,636,945 and 3,839,297 (absorbable sutures fabricated from glycolide-lactide copolyesters), U.S. Pat. No. 4,224,946 (sutures made from polyether-polyester block copolymers), U.S. Pat. No. 2,226,529 (sutures made from polyamides), U.S. Pat. No. 4,343,931 (sutures made from poly(esteramides)), U.S. Pat. No. 4,578,451 (sutures made from polyetheramides) and U.S. Pat. No. 3,454,011 (sutures made from Spandex polyurethane block copolymers).
Knitted and woven fabrics constructed from a variety of synthetic fibers and the use of the fabrics in surgical repair are known from, among others, U.S. Pat. Nos. 3,054,406; 3,124,136; 4,193,137; 4,347,847; 4,452,245; 4,520,821; 4,633,873; 4,652,264; 4,655,221; 4,838,884; and 5,002,551; EPA 334,046; and Wantz, "Atlas of Hernia Surgery", Raven Press, 1991.
Ionomer resins are known, inter alia, from U.S. Pat. Nos. 3,264,272, 3,322,734 and 3,404,134.
Blends of ionomer resins and elastomers such as ethylene/propylene copolymer, butadiene/styrene copolymer, etc., are known from U.S. Pat. No. 3,454,676.
Fibers manufactured from ionomer resins employing a wet or dry spinning process are known from U.S. Pat. Nos. 4,172,820, 4,226,751, 4,259,284 and 4,343,859. The fibers have use in clothing, carpeting and similar applications.